[sdiy] peltier elements dimensioning

[Czech Martin]

If I put in 80W of heat power into a case, temperature will raise from
25C to 60C. This can be understood as thermal resistance of 0.44K/W.

If I use a peltier element with 20W pump power (giving about 40W
total power consumption since most elements seem to output
only 0.5 of total power as pump power) 
this should lead to 8.8K cooling, i.e. down from 25C to 17C.
In the same way 40W pump power will cool 17.5K, i.e. @ 25 down to 7.5C.
The total power consumption will be arround 80W then.

Is it usal to spec total power and pump power?
Will the element behave close to ohmic resistor?


Is this near to correct? Or did I make a stupid mistake?


m.c.